when applying the brakes it may give off a sound from the vacuum entering the diaphragm. I dont thnk that a sound would be a vacuum leak as one that large would effect the way the truck runs, like idling fast or dropping down when you accelerate. It may be just the normal sound of the diaphragm Or if you have a vacuum pump that may not be working.
May 27, 2010 at 2:53 PM